In the hospital setting, prophylactic
acid suppression is an important part of care for many
critically ill patients. It may also prevent rebleeding in patients admitted with acute upper gastrointestinal tract
bleeding. Effective treatments for these conditions stemmed from our increased understanding of the gastric acid secretory pathway and target pH values. The late 1970s saw the introduction of histamine2-receptor antagonists (H2RAs), which partially suppress basal and meal-stimulated
acid secretion. Some of these agents can induce an intragastric pH greater than 3, lasting for approximately 10 hours/day when given twice/day at recommended doses. This level of
acid suppression can facilitate healing of
duodenal ulcers but has limited efficacy for other indications (e.g., gastrointestinal bleed). In the late 1980s a more potent class of
acid-suppressing agents was developed,
proton pump inhibitors (PPIs). The PPIs can induce an intragastric pH above 3 lasting for approximately 17 hours/day, and an intragastric pH above 5 for approximately 9 hours/day after once-daily
oral administration of recommended doses. It is possible to attain even higher target pH values with large doses and with continuous
intravenous infusion. Thus, PPIs are agents of choice for treatment of many
acid-related disorders including
peptic ulcer disease and moderate-to-severe
gastroesophageal reflux disease, and for prevention of rebleeding in patients with upper gastrointestinal
bleeding. Availability of an intravenous formulation,
pantoprazole, enables hospitalized patients for whom
oral administration is not feasible to benefit from the superior potency of PPIs. Preliminary data suggest that intravenous PPIs may be more effective than H2RA prophylaxis against stress-related
ulcer bleeding for
intensive care patients and should facilitate healing in those with
bleeding ulcers of the upper gastrointestinal tract.